This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 26 |
| 6 | 76 |
| 7 | 232 |
| 8 | 764 |
| 9 | 2619 |
| 10 | 9486 |
| 11 | 35596 |
| 12 | 139392 |
| 13 | 562848 |
| 14 | 2352064 |
| 15 | 10092160 |
| 16 | 44546320 |
| 17 | 201158620 |
| 18 | 930213752 |
| 19 | 4387327088 |
| 20 | 21115314916 |
| 21 | 103386386516 |
| 22 | 515097746072 |
| 23 | 2605341147472 |
| 24 | 13378787264584 |
| 25 | 69622529312665 |
| 26 | 367161088308490 |
| 27 | 1959294979429380 |